# Electronic properties of {\alpha}-RuCl3 in proximity to graphene

## TL;DR

This study investigates how placing {}RuCl3 near graphene affects its electronic and magnetic properties, revealing strain-induced doping, an insulator-metal transition, and enhanced Kitaev interactions, with implications for exotic superconductivity.

## Contribution

The paper demonstrates that proximity to graphene induces strain and doping in {}RuCl3, significantly enhancing Kitaev interactions and enabling potential metallic or superconducting states.

## Key findings

- {}RuCl3 becomes lightly electron-doped and graphene hole-doped due to charge transfer.
- An insulator to metal transition occurs in {}RuCl3 near the Fermi energy.
- Kitaev interactions are increased by over 50% in strained {}RuCl3 monolayers.

## Abstract

In the pursuit of developing routes to enhance magnetic Kitaev interactions in {\alpha}-RuCl3, as well as probing doping effects, we investigate the electronic properties of {\alpha}-RuCl3 in proximity to graphene. We study {\alpha}-RuCl3/graphene heterostructures via ab initio density functional theory calculations, Wannier projection and non-perturbative exact diagonalization methods. We show that {\alpha}-RuCl3 becomes strained when placed on graphene and charge transfer occurs between the two layers, making {\alpha}-RuCl3 (graphene) lightly electron-doped (hole-doped). This gives rise to an insulator to metal transition in {\alpha}-RuCl3 with the Fermi energy located close to the bottom of the upper Hubbard band of the t2g manifold. These results suggest the possibility of realizing metallic and even exotic superconducting states. Moreover, we show that in the strained {\alpha}-RuCl3 monolayer the Kitaev interactions are enhanced by more than 50% compared to the unstrained bulk structure. Finally, we discuss scenarios related to transport experiments in {\alpha}-RuCl3/graphene heterostructures.